ELECTROCHEMICAL-BEHAVIOR OF ALCL3 IN PROPYLENE CARBONATE AT ROOM-TEMPERATURE

The electrochemical behavior of AlCl3 in propylene carbonate at 25 deg rees C was studied by triangular sweep voltammetry with platinum elect rodes. The overall mechanism is in agreement with the well-known ErCi reaction scheme: [GRAPHICS] with O: AI(III), where the electrochemical step reflects a quasi-reversible behavior and the following chemical reaction shows a first-order rate, The apparent electron transfer coef ficient alpha n(alpha) (where alpha is the transfer coefficient, and n (alpha) is the number of electrons exchanged in the rate determining s tep) is evaluated at 0.24+/-0.055 by semi-integration of the voltammet ric E = f(I) curves. The first-order rate constant of the chemical ste p was calculated and found to be k(f) congruent to 5/sec. The absence of aluminum deposited on the cathode was confirmed by scanning electro n microscopy on electrodes that were polarized at E = -0.65 V/RE for a s many as eight hr.